Odd pipe size

[Dave]

A friend of mine if fitting a new bath. The problem is that one of the pipes he needs to join to looks like 22mm but is actually a little bigger. I don't think it's imperial 3/4 inch pipe as I would expect that would be smaller not bigger than 22mm.

It's only a fraction too big, the nut from a compression fitting will go on if hammered on but then it's too tight on the pipe to turn and do up and the olive will not go on at all. Solder fittings will no go on either.

Anyone got any idea how to deal with this ?

[EricP]

Try reaming the inside of the compression nut out with a sander in a dremel type tool. I had to do some 15mm like that. It doesn't take much reaming to enlarge the hole a fraction, just try to get it off evenly all round.

[Dave]

That sounds reasonable, but if I do the same to the olive, then it's probably not going to seal properly, is it ?

[Chip]

On Thu, 30 Jun 2005 20:53:38 +0100,it is alleged that "Dave" spake thusly in uk.d-i-y:

Just a guess, but could the pipe be 7/8" outside diameter? While I have never personally heard of that size being used, it's just a hair over 22mm. If so, your local plumber's merchant *may* have olives for it.

[fred]

In article , Dave writes

A bit bulky/expensive but a 25mm MDPE connector with one or more copper adaptor sets should do the job. The adaptor set uses rubber as a the seal so will hopefully accommodate the slightly larger pipe. See:

code: 9853 for straight or other variants for Ts etc with adaptor set 9939 on:

[Ed Sirett]

I wonder if the pipe is slightly out of round?

[EricP]

Olive too small as well? You can stretch them a bit by heating and pushing a bit of pipe into them. Pity there isn't a short length of the problem pipe available, you could have used that. The olive is very soft and cheap so you can experiment.

[Autolycus]

A few years ago I came across a similar problem with 1/2" pipe which wasn't the 1/2" pipe we all know and love and which can be shoved into

15mm fittings. It turned out that in that particular area of Derby, for a period in the thirties, this oddly thick-walled pipe was commonplace. Most of the local builders' merchants had never heard of it, but one local firm, in business since Adam was a lad, knew all about it and duly produced some adaptors from a dusty shelf.

So, either try the oldest-established plumbers' merchant in the area, or try a 22mm plastic pushfit coupler, in the hope that it has enough "give" in its O ring, or look for one of those magic universal couplers that fit stuff like black alkathene, lead, or even iron pipe.

[Christian McArdle]

Have you tried a pushfit coupler?

Christian.